Macrosomia, prematurity, perinatal mortality, and congenital malformations are more common in infants of diabetic mothers than in infants of nondiabetic mothers. Offspring of diabetic women are also at an increased risk of developing obesity and glucose intolerance during childhood and young adulthood. The purposes of the project are to identify diabetes and impaired glucose tolerance during pregnancy in women in the Gila River Indian Community, to determine the effects of abnormal glucose tolerance on outcome of the pregnancy, and to determine long term prognosis for the women and their offspring. The diabetes status of every woman is determined at two-yearly intervals and during the third trimester of each pregnancy. The characteristics of women who have diabetes or impaired glucose tolerance during the pregnancy are compared to those of women who are normal during the pregnancy and subsequently develop diabetes and to those of women who remain normal. At birth, cord blood has been collected for determination or glycosylated fetal hemoglobin and proinsulin. These women and their offspring, after the age of 5 years, are followed at two- yearly intervals. It has been previously reported that offspring of diabetic women have more diabetes and more obesity than offspring of nondiabetic and prediabetic women. Hand and wrist x- rays have been evaluated for bone age among the offspring of diabetic women and found to be advanced relative to the bone age in the offspring of nondiabetic and prediabetic women. The findings suggest that the intrauterine environment, in addition to being an important determinant of the development of diabetes and of obesity, is also important in determining skeletal development.